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Tandem-rotor helicopters have the advantage of being able to hold more weight with shorter blades, since there are two sets. However, the rear rotor works in the aerodynamic shadow of the front rotor, which reduces its efficiency. This loss can be minimized by increasing the distance between the two
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Tandem-rotor helicopters typically require less power to hover and achieve low-speed flight as compared to single-rotor helicopters. Both configurations typically require the same power to achieve high-speed flight.
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is applied to each rotor; decreasing the lift produced at one end, while increasing lift at the opposite end, effectively tilting the helicopter forward or back.
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The two rotors are linked by a transmission that ensures the rotors are synchronized and do not hit each other, even during an engine failure.
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108:, whereas a single-rotor helicopter uses some of the engine power to counter the torque. An alternative is to mount two rotors in a
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rotor hubs, and by elevating one hub over the other. Tandem-rotor helicopters tend to have a lower
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to each rotor, effectively pulling both ends of the helicopter in opposite directions. To achieve
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movement produced by the single large rotor. This is commonly accomplished by a
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configuration. The first successful tandem-rotor helicopter was built by
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445:"US Army FM 3-04.203 Fundamentals of Flight; page 1-33, para 1-81, 1-82"
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Principles of helicopter aerodynamics by J. Gordon
Leishman p. 73.
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227:(1961) - most-produced tandem-rotor helicopter (over 1,200 built)
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Single-rotor helicopters need a mechanism to neutralize the
127:. Disadvantages of the tandem rotor system are a complex
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Currently this configuration is mainly used for large
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assemblies mounted one in front of the other in the
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119:Advantages of the tandem rotor system are a larger
478:Rotary Wing Aerodynamics, W.Z. Stepniewski, p. 185
96:systems. Tandem-rotor helicopters, however, use
27:Helicopter with two horizontal rotor assemblies
434:Art of the helicopter by John Watkinson, p. 13
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411:"FM 1-514 CHPTR 3 - Rotor System Operation"
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245:(1960), military version of Vertol 107-II
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100:, with each cancelling out the other's
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141:by applying opposite left and right
131:and the need for two large rotors.
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161:than single-rotor helicopters.
243:Boeing Vertol CH-46 Sea Knight
1:
371:Intermeshing-rotor helicopter
137:Tandem-rotor designs achieve
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386:Transverse-rotor aircraft
509:Tandem rotor helicopters
212:Central Air Force Museum
257:Boeing Vertol Model 234
253:(1970s - not completed)
98:counter-rotating rotors
366:Coaxial-rotor aircraft
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125:longitudinal stability
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38:
504:Helicopter components
331:/HUP Retriever (1952)
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51:tandem-rotor aircraft
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33:
335:Piasecki HRP Rescuer
251:Boeing Vertol XCH-62
237:Boeing Vertol 107-II
225:Boeing CH-47 Chinook
198:B in the early 1960s
181:Boeing Vertol 107-II
178:Columbia Helicopters
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293:Filper Helicopter
263:Bristol Belvedere
121:center of gravity
70:cargo helicopters
16:(Redirected from
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413:. Archived from
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347:Rotorcraft XR-11
269:Bristol Type 173
231:Boeing Model 360
63:horizontal plane
59:helicopter rotor
36:CH-46 Sea Knight
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353:Yakovlev Yak-24
305:Jovair Sedan 4A
287:Filper Beta 400
281:Filper Beta 200
208:Yakovlev Yak-24
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123:range and good
114:Nicolas Florine
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57:with two large
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90:coaxial rotors
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34:Boeing Vertol
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417:on 2014-02-18
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329:Piasecki H-25
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323:Piasecki H-21
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317:Piasecki H-16
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419:. Retrieved
415:the original
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159:disk loading
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129:transmission
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18:Tandem-rotor
149:, opposite
498:Categories
421:2017-12-03
392:References
376:Rotorcraft
299:HERC JOV-3
185:Boeing 234
151:collective
92:, and the
86:tail rotor
381:Tiltrotor
275:Chu CJC-3
116:in 1927.
45:Animation
360:See also
219:Bell HSL
169:Examples
55:aircraft
239:(1958)
110:coaxial
355:(1952)
349:(1947)
343:(1948)
337:(1945)
325:(1949)
319:(1953)
313:(1951)
307:(1963)
301:(1948)
295:(1965)
289:(1967)
283:(1966)
277:(1952)
271:(1952)
265:(1958)
259:(1981)
233:(1987)
221:(1953)
143:cyclic
102:torque
82:yawing
76:Design
53:is an
448:(PDF)
147:pitch
94:NOTAR
183:and
106:lift
210:at
139:yaw
500::
400:^
206:A
194:A
88:,
72:.
65:.
49:A
450:.
424:.
20:)
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